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Discussion

Let us know what you think about any topic related to the Sierra Nevada
Adaptive Management Project in the forums below. The Principal
Investigators on the UC Science Team cannot answer every post, but they
will read all comments in their areas, and respond to comments as a
group at each quarterly meeting. We greatly value your input!

The following are questions and responses regarding the CA spotted owl:
Q1:Since 1993, the owl team stated that they have surveyed roughly 90% of the
DSA each year. This was determined by placing a 1/2 mile buffer around each of
the recorded survey points. Would it be possible to determine the % "covered"
for each year 1986 through 1992 using the same methodology? If so, can the
percentage of coverage be provided?

A1: We previously estimated the survey coverage on the Eldorado Density Study
Area (EDSA) for the years 1989-1992:

1989: 78%
1990: 82%
1991: 86%
1992: 91%

Although the coverage was reasonably high in these years, many portions of the
EDSA were only surveyed once per year from 1989-1992 because we did not have
sufficient funding to hire an adequate number of technicians. This lack of
survey effort made it more likely that we failed to detect owls that were
actually present. 1993 was the first year that we conducted more than 1 survey
at >90% of our survey stations.

Q2:Could the occupancy analysis be run on the owl sites that were first found in
the study area from ~1986 through 1992? Has the occupancy rate for those owls
sites dropped as well? Premise of question: The range -wide high reproductive
year of 1992, (most likely due to abundance of prey and very mild spring
weather) also lead to a high survival rate (young and adult) and potentially a
population that was above the carrying capacity of the landscape. The
population in 1993 with nearly 100% occupancy has been slowly adjusting back
"down" to the “normal or potential” carrying capacity of this landscape.

A2: We appreciate Mr. Brink’s suggestion, but we currently lack the time and
resources to pursue an occupancy analysis for the years 1986-1992. As we stated
at the Owl IT meeting in August, we chose 1993 as the starting point of our
analysis because it was scientifically defensible. In other words, a peer
reviewer could assert that any observed occupancy trends were confounded by
changes in survey effort if we used data prior to 1993.

We also question his premise that a single year (1992) of high reproductive
output is still affecting our study population 20 years later. Spotted owls are
long-lived, but with an annual survival rate of ≈ 0.83, it is unlikely that a
birth pulse would continue to influence population trends 20 years after the
pulse.

The following questions have been submitted by Steve Brink in response to the
SNAMP Owl team's IT meeting in August 2012:

Q1)Since 1993, the owl team stated that they have surveyed roughly 90% of the
DSA each year. This was determined by placing a 1/2 mile buffer around each of
the recorded survey points. Would it be possible to determine the % "covered"
for each year 1986 through 1992 using the same methodology? If so, can the
percentage of coverage be provided?

Q2)Could the occupancy analysis be run on the owl sites that were first found in
the study area from ~1986 through 1992? Has the occupancy rate for those owls
sites dropped as well? Premise of question: The range -wide high reproductive
year of 1992, (most likely due to abundance of prey and very mild spring
weather) also lead to a high survival rate (young and adult) and potentially a
population that was above the carrying capacity of the landscape. The
population in 1993 with nearly 100% occupancy has been slowly adjusting back
"down" to the “normal or potential” carrying capacity of this landscape.

The following response is from the SNAMP Owl team to questions submitted by
Steve Brink after the IT meeting of 8/23/2012:

Q1:Looking again at the Lambda graph, it’s interesting that the downward slope
of the line is nearly constant. I should have thought about the 2001 Star Fire
when Pat Ferrell, Eldorado NF Contracting Officer, asked a question about it.
The Star Fire burned 16,900 acres in Aug-Sept. 2001, about 2,400 acres of which
were on the Georgetown Ranger District. Following the fire, the USFS concluded
that the two HRCAS, in which PAC055 and PAC075 were located, were essentially
destroyed and recommended deleting both PACs from the Forest plan. Further,
about 70% of the total acres burned in the Fire were of high severity. So, how
is it that the Star Fire had absolutely no affect on the owls?

Response: First, recall that Doug noted that the estimates for lambda are based
on model averaging (the average estimate of several models), which results in
the smooth (“constant”) curve to which you refer. As long as the declining
trend is not abrupt, it will appear relatively smooth despite slight variation
in the annual estimates. Second, the two owl territories affected by the Star
Fire were Regional territories, and the lambda analysis only included owl
territories on the Density Study Area. Even if the two owl territories affected
by the fire had been located on the Density Study Area, the observed impact
would not have been dramatic because there are 45 owl territories on the density
study area.
In addition, we note that about 2,500 acres did burn on the Eldorado Density
Study area during the Star Fire. This burn affected 3 owl territories on the
density study, but all have been occupied at least once since the fire.

Q2: Because soil site classification could be used as a surrogate for the
overall “primary productivity” of a forest, will the samples for the control and
“treatment” areas be stratified? The premise being that owls in highly
productive forests will perform better under both the control and “treatment”
conditions, and likewise owls on less productive forests will underperform under
control or treatment scenarios.

Response: This was suggested in the context of including “abiotic” factors as
covariates in our analysis, which we think is a good idea. The idea of
including soil type is a good one and we will consider that thoroughly for our
list of covariates.

Q3: It’s still unclear to me why the Team is not opportunistic and looking to
tease out why Owls had very high reproductive success in 1992. Using the 1993
data, and not using 1992, doesn’t seem intuitive given Rocky’s premise that
CSO’s live a long time and have an evolutionary strategy that is opportunistic
for reproduction. How can that be justified?

Response: The owl team has often wondered why there was such high reproduction
in that year. The problem is that there is that there have been no other years
such as 1992 to make comparisons. In other words, if you found several factors
that were different in this year relative to other years, how would you
distinguish which was consistent in terms of its importance to owls? One needs
to have multiple examples of unique events to detect a pattern. In addition,
1993 was the first year that we had good aerial photography for the entire study
area and adequate sampling effort to have confidence in detecting reproduction
and a sufficient number of surveys over the entire study area. We note also,
that unlike what was implied in our presentation, we do have air photos prior to
1993 but they are not seamless digitized photos as in 1993. Thus, it is quite
time consuming to work with these other photos. It is important for the record
to note that all of the effort to create vegetation maps by the owl team for the
past dozen years in order to assess impacts has been done, until last year,
without funding. That is, we have no allocated money to engage in this
activity, but all the owl investigators have devoted their own time to create
such maps because we realize the importance of the information. We continue to
assess sources of air photographs that are easily used and welcome any help the
SNAMP stakeholders are able to offer.

Q4: Given how robust the IPM is, why wouldn’t Doug include ALL of the owl data
that the Team has including:
1)The discrepancies related to the 8 birds that were counted in the occupancy
but not as part of the population and likewise the other 4 birds that resisted
capture?
2)The 1992 reproduction data since it is congruent with Rocky’s premise that the
evolutionary strategy of the owl is to be long lived and be opportunistic for
reproduction?
3)Running a comparison with and without the 1992 data?

Response: “All” of the birds, including the ones referred to in part 1 of this
question, are incorporated into the IPM through the count data. The count data
are the number of birds detected each year on the Density Study Area, regardless
of whether the birds are marked or unmarked. Doug chose 1993 as the starting
year for all of his population trend analyses because that was the first year
that we achieved adequate survey coverage of the Density Study Area. As Doug
discussed, it is critical that the study area be consistent in size when
assessing population trends because the number of birds in the population is a
direct function of the size of the study area.
The 1992 data are consistent with the hypothesis that spotted owls have evolved
a “bet hedger” life history strategy, but so are many other features of their
life history (such as long life span, low fecundity). So the 1992 data are
interesting but they do not make or break any analysis we do. They are
interesting and we are curious, like you, as to why we have not seen similarly
high reproduction years since then. However, these data as a single event do
not provide insight into changes in owl populations other than to demonstrate
that unusually high years of reproduction do occur infrequently.

The following questions have been submitted by Steve Brink in response to the
Owl IT meeting on 8/23/2012:

Q1: Looking again at the Lambda graph, it’s interesting that the downward slope
of the line is nearly constant. I should have thought about the 2001 Star Fire
when Pat Ferrell, Eldorado NF Contracting Officer, asked a question about it.
The Star Fire burned 16,900 acres in Aug-Sept. 2001, about 2,400 acres of which
were on the Georgetown Ranger District. Following the fire, the USFS concluded
that the two HRCAS, in which PAC055 and PAC075 were located, were essentially
destroyed and recommended deleting both PACs from the Forest plan. Further,
about 70% of the total acres burned in the Fire were of high severity. So, how
is it that the Star Fire had absolutely no affect on the owls ?

Q2: Because soil site classification could be used as a surrogate for the
overall “primary productivity” of a forest, will the samples for the control and
“treatment” areas be stratified? The premise being that owls in highly
productive forests will perform better under both the control and “treatment”
conditions, and likewise owls on less productive forests will underperform under
control or treatment scenarios.

Q3: It’s still unclear to me why the Team is not opportunistic and looking to
tease out why Owls had very high reproductive success in 1992. Using the 1993
data, and not using 1992, doesn’t seem intuitive given Rocky’s premise that
CSO’s live a long time and have an evolutionary strategy that is opportunistic
for reproduction. How can that be justified?

Q4: Given how robust the IPM is, why wouldn’t Doug include ALL of the owl data
that the Team has including:
1) The discrepancies related to the 8 birds that were counted in the occupancy
but not as part of the population and likewise the other 4 birds that resisted
capture?
2) The 1992 reproduction data since it is congruent with Rocky’s premise that
the evolutionary strategy of the owl is to be long lived and be opportunistic
for reproduction?
3) Running a comparison with and without the 1992 data?

Can you provide a "working" definition the researchers are using for spotted owl
occupancy. Is it simply occupancy (i.e. owl presence) or is it pair occupancy,
or something else? Thank you for your time and consideration with this
question.
Kevin Roberts
Wildlife Biologist
Sierra Pacific Industries

The determination for occupancy is the presence or absence of an owl that is
corrected for detection probability. It can be a single owl or a pair.
Rocky Gutierrez - SNAMP Owl team
Kim Ingram - PPT team

Prescribed Burning for Beargrass Enhancement on the Last Chance Project
November 3, 2011
"I was forwarded notice about a planned "Bear Grass burn area" at the Last
Chance study site. Do you have information about the objectives/prescription for
that particular treatment as well as what kinds of monitoring data will be
collected pre/post to evaluate the effects? My colleague, Frank Lake, and I are
interested in gathering information about fire effects on cultural resources as
well as monitoring prescribed fires on the quality of those resources for
cultural uses. Thank you, Jonathan Long Pacific Southwest Research Station."
Bear grass Xerophyllum tenax, is a fire-tolerant species that needs periodic
fire to produce new growth, and is often the first plant to re-sprout after a
fire. Low intensity fire eliminates dead, dry blades from the previous year’s
growth and encourages supple new leaf growth that is used by traditional weavers
to make baskets, hats, and other items.
Treatment Objectives
1. Conduct a low intensity burn consuming 80% to100% of the above-surface bear
grass leaves to stimulate re-sprouting of new leaves for weaving.
2. Keep unwanted vegetation from encroaching upon the gathering site.
3. Maintain a minimum of forty percent effective soil cover.
Fire Behavior Prescription
1. Flame lengths from 3 to 4 feet.
2. Effective wind speed from 6 to 7 miles per hour.
3. Scorch height from 3 to 12 feet.
4. Forward spread rate from 238 to 508 feet per hour.
5. Backing spread rate from 13 to 20 feet per hour.
6. Spotting distance not to exceed 1584 feet.
Monitoring
On November 2, 2011 2.9 acres of the designated beargrass enhancement area
within the Last Chance Integrated Vegetation Management Project were ignited.
Preliminary observations indicate that all of the treatment objectives were
successfully met. While the Forest Service did not collect pre-burn data for
this specific burn area, adjacent unburned fuels are representative of the
pre-existing condition.
For additional information, contact:
Larry Peabody, Fuels Specialist
Tahoe National Forest, American River Ranger District
22830 Foresthill Road. Foresthill CA 95631
(530) 367 2224 x 240

At the annual SNAMP meeting, I explicitly stated that I did not know what is
causing this recent (past 10 years) owl decline. Our research suggests that the
decline is real based on two different estimators producing the same result. I
was also asked by a participant at the meeting if fuel treatments might be the
cause of the decline and I said that I did not know because there were other
factors that might be involved such as clear cutting on private land. By
logical extension, this would apply to home development as well, as you
suggested in your letter. Recall that the owl component of Last Chance includes
the entire Eldorado spotted owl density study area, which encompasses a much
larger area than Last Chance and has many more owl territories. Because of the
uncertainty about the cause of the decline, the owl team has proposed a
retrospective study to examine all observable changes in owl habitat that were
due to disturbance. Presumably this would allow us to account for different
types of disturbance, which would address one of your concerns. Our inference
would be restricted to our study areas because we are not measuring change or
monitoring owls throughout Eldorado County although our study areas might be a
representative sample of this population. In addition, because of severe budget
limitations, I doubt that our study could be expanded to include all of Eldorado
County.

The following comments and questions were asked by Lorna Dobrovolny from CA
Dept. of Fish and Game:

'I work with Cal Fire foresters on wildlife issues in El Dorado County resulting
from forest fuel reduction projects. There are no longer any DFG staff on
timber harvesting review teams as a result of state budget cut-backs.
California spotted owl has only a Species of Special Concern status. Thus, very
limited regulatory protection from projects on private forest lands. I was very
interested and concerned about Rocky's findings regarding spotted owls. There
has been substantial timber harvesting and population expansion in the early to
mid 2000s during the housing boom in El Dorado County. I'm not sure how the
SNAMP research can outline a study plan to definitively show that it's the Last
Chance fuel break that would be impacting the birds, given a demonstrated
existing decline. Do you know how this is going to be accounted for? Also, the
USFS and CAL FIRE have given much grant money to forest land owners in the past,
mostly to tie together ridgetop fuel breaks for fire prevention. Most of that
work was mastication, the result of which may not offer spotted owls suitable
habitat."

The following question was asked of the Fire & Forest Ecosystem Health team by
Bill Tripp, Eco-cultural Restoration Specialist of the Karuk Tribe, Dept. of
Natural Resources:

I would appreciate it if someone could ask if they (the Fire & Forest Ecosystem
Health team) are looking at how traditional gathering of Pine roots could
potentially contribute to enhanced root production and associated long term
below ground carbon storage and expedited growth and associated above ground
carbon storage. This would help to provide documentation on the benefits and
sustainability of traditional gathering as an ecosystem service and/or resource
benefit that can be attributed to management actions where such traditional
gathering is occurring or can otherwise be authorized to occur freely. In
addition, a similar and connected activity in relation to gathering in Pine
stands would be the effects on the quality and quantity of Pine nuts in relation
to management actions. It is my understanding that pine nuts were historically
a major component of subsistence and trade amongst Native Americans in the
Sierra Nevada’s, and pine roots were a primary material in construction of the
baskets utilized in the collection of that resource. There are likely
additional plants associated with that ecotype that are utilized in the
construction of these baskets that should be enhanced in the management of Pine
stands and adjacent ecotypes within Sierra Nevada landscapes. The information
on resources utilized in the construction of these baskets is likely available
from local Tribes, traditional practitioners, tribal elders, and/or museums.
Just food for thought.... Thank you,

The following concerns and comments were brought up from a general public
participant after the UC Water Team field trip to Duncan Peak at the Last Chance
study site. The UC Water Teams response follows.

"Thanks for allowing me to attend the field trip to Duncan Peak. Good
timing....getting up there before this storm.
I have one small concern. When there is a lot of snowmobilers out, those poles
(met stations) won't be that easy to see. I think that they should be painted a
bright orange on top to help for visibility. I mentioned it to the guy who was
leading us to the different sensor sites... He said that they (snowmobilers)
wouldn't be going that fast & would see them.
I don't think that he understands that the extreme snowmobilers around here go
very fast on the sides of the mountains, they don't stick to groomed trails; &
are out at night sometimes in major storms...not just during the day.
Although I agree that someone probably will not be hitting a sensor pole, it
wouldn't hurt to make them more visible."
Sincerely, Rita Moriarty

"Painting the poles orange would certainly make them more visible to
snowmobilers...but my concern is that they would also be extremely visible to
everyone else and make them very susceptible to vandalism. I also think that the
number of trees surrounding most of our poles would not enable snowmobilers to
go very fast around most of our installations. I have seen snowmobile tracks
around our previously installed equipment, and they all purposefully avoid the
poles. The solar panels on the top make them fairly visible to anyone close by
in most conditions. While there are some snowmobilers that do go out at night
and in blizzards, that is not recommended by, or for anyone and they do so at
their own risk. Furthermore, all terrain covered by snowmobilers is supposed to
be reviewed every time before any fast or difficult snowmobiling, due to changes
in snow condition, along with any small trees, sticks, logs (or poles!) sticking
up that may not be visible at fast speeds or from far away.

I appreciate the concern that Rita has shown for the snowmobilers out there (as
we are some of them). We certainly don't want anyone getting hurt or injured
from our installations. However, I believe that in most normal conditions our
installations will not cause a problem for safe snowmobiling, and we cannot
control the actions of those riders that choose unsafe snowmobiling practices."

Thanks,
~Phil Saksa
UC Water Team

"Hi All,
I really didn't think about vandalism & wouldn't think that it would be a high
priority in winter. Snowmobilers are normally just interested in riding.
When you put up any extensions, it might be possible to flag or paint the tops
in just the sites that are in the open . That way it isn't allot of extra work
for the team.
I just mentioned the visibility of poles because you said that if the people on
the field trip thought of anything to let you know. I feel that visibility
could be important & needed to address that issue."
Thanks for listening. Rita Moriarty